32VFD Variable Frequency Drives for Centrifugal Chillers

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1 32VFD 32VFD Variable Frequency Drives for Centrifugal Chillers ENERGY-SAVING CONTROL FOR CENTRIFUGAL CHILLERS

2 Reduce energy consumption in your existing centrifugal chiller Your chiller was specified to meet peak cooling loads to keep your building at a comfortable temperature, even on the hottest days. Yet, you may be surprised how seldom your chiller actually runs at peak capacity. In fact, most centrifugal chillers run at less than full-load capacity 90% or more of the time. Part-load efficiencies can be improved by utilizing a variable frequency drive (VFD) to control the motor speed of a chiller to match system load requirements, resulting in dramatic energy savings. Carrier s 32VFD Retrofit is a complete, pre-engineered package which fully integrates a variable frequency drive with Carrier s proven Product Integrated Controls (PIC). The VFD allows you to vary the speed of the chiller at off-design conditions by controlling the voltage and frequency of the electrical power to its compressor motor, significantly lowering energy consumption. The 32VFD Retrofit package interfaces with the existing chiller s PIC control sytem to provide the necessary communications and interlocked protection required for reliable, trouble-free operation of the chiller. Carrier s control system optimizes chiller part load performance by simultaneously regulating the compressor s motor speed and inlet guide vane position to maximize total system efficiency. Additionally, it continuously monitors and protects against any abnormal operating conditions. The application of a 32VFD Retrofit will increase the operating efficiency of a chiller, typically resulting in a payback of two to three years. After payback, you ll continue to realize savings month after month, over the remaining life of your chiller. The Carrier 32VFD Retrofit s added control and wide array of standard features combine to make it the perfect solution to reduce energy consumption in your existing centrifugal chiller.

3 Lowers Peak Demand Charges Along with lowering energy consumption, a VFD delivers other cost saving benefits, such as the possible elimination of electrical demand charges and qualification for utility rebates. Electrical demand charges may be reduced because the motor will always start at low frequencies and maintain inrush current at or below full load amps. Plus, many utilities offer rebates as an incentive to install a variable frequency drive. These rebates can substantially reduce the payback period for installations. (Contact your power company for more information on utility rebates.) Reduces Motor Stress Another important benefit of a VFD installation is that it reduces stress on your chiller s motor. By providing soft start and controlled acceleration, the motor is no longer subject to the electrical and mechanical stress normally present during start-up. A VFD also protects your chiller motor from the destructive effects of power surges and fluctuations, as well as electrical power line disturbances, resulting in increased operating life of the chiller and lower maintenance costs. How a Variable Frequency Drive Retrofit Works Power Supply Inlet Guide Vane Position Reference VFD Output to Compressor Motor PIC VFD VFD Speed Reference Temperature Sensor Inputs Carrier s VFD Retrofit integrates with Carrier s Product Integrated Controls (PIC) to control both compressor motor speed and inlet guide vane position during part-load conditions.

4 Delivers Quieter Operation Much of the noise produced by a centrifugal chiller is due to the refrigerant being discharged at a high speed into the condenser. A VFD causes a centrifugal chiller to be quieter by slowing down the compressor and reducing refrigerant discharge velocity at lower loads in off-peak operation. This means your building occupants will notice less noise and vibration, especially important for applications such as offices, retail stores, schools, libraries and hospitals. Modernization of your existing chiller may also include an upgrade to Carrier s advanced microprocessor-based controls. To minimize downtime, a refrigerant conversion, PIC update and VFD retrofit can all be performed at the same time by Carrier s experienced service technicians. Additionally, Carrier offers a complete array of services designed to improve the performance of your HVAC system. These include a wide range of modernization services including diagnostics, prognostics and maintenance contracts. Advanced Diagnostics and Communications The VFD features advanced diagnostics capabilities in addition to Carrier s standard PIC chiller diagnostics. Full integration by design provides communication and troubleshooting diagnostics between the VFD and the chiller controls. Both the PIC and VFD have userfriendly interfaces that show the status of each device. Considering an Upgrade or Conversion? Whether you are upgrading a chiller for improved part-load efficiency, or converting an older chiller from a CFC-based refrigerant to HFC-134a, it s a perfect time to benefit from the energy savings of a Carrier VFD retrofit package. Not only will you be protecting the environment by using a chlorine-free refrigerant, you ll also be improving your bottom line by using less energy. The combination will result in significantly lower operating costs. Carrier s Variable Frequency Drive Retrofit will help lower energy and operating costs in a wide variety of chiller applications.

5 Put state-of-the-art, energy-saving control at your fingertips. Standard Design Features The 32VFD is a solid-state control designed specifically to integrate with Carrier s centrifugal chillers. The 32VFD retrofit package interfaces to the existing chiller s microprocessor control system providing state-of-the-art technology with advanced protective features to help avoid or minimize chiller downtime. These include overvoltage, undervoltage, overcurrent, short circuit and ground fault protection. Other features include: High horsepower range from HP at 460 volts, 3 phase. Input Line Fuses provide short circuit protection and high interruption capacity. Standard circuit breaker with shunt trip provides positive disconnect of incoming power during a fault condition. Built-in DC link choke improves input power factor and input line harmonics. Personal lock-out code to limit programming access. NEMA-1, Type-12 fan and filter enclosure protects the power electronics for a long, useful life. 180% instantaneous overcurrent trip prevents long-term overloads and helps protect life of compressor motor. Door-mounted digital key pad with LCD display contains on-line diagnostics and an easy, quick set up key to access the most common drive parameters. Utilizes the latest PWM/IGBT, insulated gate bipolar transistor, technology. Fast switching devices allow the VFD to protect itself, thereby increasing reliability. Data stored in non-volatile memory means no loss of pre-fault troubleshooting information, even after power is restored. Soft start capability eliminates demand peaks during start-up UL & cul certification ensures safety to worldwide industry standards. Optional Design Features These options can simplify the use of your 32VFD and improve its system protection capabilities. 12-pulse option includes a phase shifting transformer to meet IEEE-519 current and voltage standards. Emergency contactor bypass guarantees uptime for critical applications Serial communications link allows easy access to all monitoring and diagnostic capabilities.

6 Technical Summary Motor Shaft Power Range HP ( kw) voltage 3 phase, 380/415/440/480 V, + 10% Supply frequency 45 Hz - 63 Hz power factor fundamental power factor > 0.96 overload 150% full load current for 60s, giving up to 160% related motor torque at breakway. Output voltage 3 phase, compensated to give correct motor fluxing to a maximum voltage level equal to the supply voltage at the drive chassis terminals. frequency Hz (c.c to 60 Hz setting when shipped) Enclosure Protection NEMA1 (IP20) and NEMA 12 (IP54) (optional) NEMA1 type 12 fan cooled Operating Temperature -10 o C to 40 o C. Derate output current by 2% per o C above 40 o C up to 50 o C max. Altitude Up to 3300 ft to 6600 ft. derate by 10% (1000 meters to 2000 meters.) Storage Temperature -25 o C to 70 o C Humidity 5% to 95% relative humidity non-condensing. Cooling Forced air cooled, with internal fans. Local control panel - 5 key, 4 digit - on front panel of drive. Digital Control Panel Optional alphanumeric control panel - mounts on enclosure, or is hand held. Control terminals for remote control (analog and digital) wiring. Serial port. Three skip frequencies Seven preset speeds Reference sequencing Braking modes Saturation, critical, and DC injection braking Start modes Normal and auto-synchronization Main Features PID control Programmable analog inputs and PID control valves Backup control source Programmable defaults for action upon loss of control of speed reference Auto restart Programmable number of attempts up to 20 Supply loss Maintains synchronism with motor during supply dip History record Records 10 selectable drive parameters during period before a trip incidence Trip history Records 10 previous trips Maximum frequency Separate forward and reverse, 10 Hz Hz Minimum frequency Separate forward and reverse, 0 - max. Hz Acceleration rate Separate forward and reverse, 1-100s Deceleration rate Separate forward and reverse, 1-100s Motor rated voltage and frequency Main Parameters Motor rated current Current limit Voltage boost Slip compensation Start up frequency Switching frequency 2 khz khz Parameters may be protected by a security code Serial Communication RS485, 19.2 kbaud, with MODBUS ASCII/RTU, GEM80 ESP. Allows full drive control, programming, monitoring and diagnostics, including access to history record. Analog Inputs 2 inputs programmable for speed ref/pid, ref/pid feedback: 0-10V/0-20mA/4-20mA/10 - OV/20 - OmA/20-4mA Analog Outputs 2 outputs programmable for drive output frequency, current or voltage: 0-10V/O - 20mA/4-20mA/10 - OV/20 - OmA/20-4mA: unipolar or bipolar signals Digital Inputs 5 inputs: run at speed ref 1, run a speed ref 2, stop, interlock, forward/reverse: 24VDC 3 outputs programmable to include the status of the drive. Default settings are: drive healthy, drive running, drive Digital Outputs frequency. Others are: eg. drive accelerating, running at speed, running below 4Hz. Outputs are volt free relay changeover contacts. As the world leader in Heating, Ventilation and Air Conditioning, Carrier is committed to continually improving the quality of comfort we provide to our customers. But our level of responsibility extends well beyond... Carrier Corporation has identified six specific areas which directly impact how we, as a world manufacturer, balance our customers needs for comfort with the environment s needs for responsible consumption. These symbols graphically represent our six areas of concentration and will serve as visual reminders of the importance of managing our finite resources. Each one of us at Carrier Corporation believes that, for generations to come, success will not only be measured by the quality of our products and systems, but also by how we have improved the quality of life. For more information, and to evaluate your full energy saving potential with a Carrier 32VFD Retrofit, call your local Carrier representative, or CARRIER. To learn more about Carrier and its products and services, visit our site on the World Wide Web: Carrier Corporation Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice or without incurring obligations.